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Journal of environmental Sciences 2018年第6期30卷 122-129页

作者： e.A.Mann S.e.Ziegler A.Steffen N.J.O'driscoll Department of environmental Science Acadia University environmental Science Programme Memorial University of Newfoundland environment and Climate Change Canada Science and Technology Branch Air Quality Research Division

Mercury（Hg） in the Arctic is a significant concern due to its bioaccumulative and neurotoxic properties, and the sensitivity of Arctic environments. Previous research has found high levels of Hg in snowpacks with high chloride（Cl-） concentrations. We hypothesised that Cl- would increase Hg retention by decreasing Hg photoreduction to Hg（0） in melted Arctic snow. To test this, changes in Hg photoreduction kinetics in melted Alert, NU snow were quantified with changing Cl- concentration and UV intensity. Snow was collected and melted in Teflon bottles in May 2014, spiked with 0–10 μg/g Cl-, and irradiated with 3.52–5.78 W·m-2 UV（280–400 nm）radiation in a Luz Chem photoreactor. Photoreduction rate constants（k）（0.14–0.59 hr-1） had positive linear relationships with [Cl-], while photoreduced Hg amounts（Hg（Ⅱ）red） had negative linear relationships with [Cl-]（1287–64 pg in 200 g melted snow）. Varying UV and[Cl-] both altered Hg（Ⅱ）red amounts, with more efficient Hg stabilisation by Cl- at higher UV intensity, while k can be predicted by Cl- concentration and/or UV intensity, depending on experimental parameters. Overall, with future projections for greater snowpack Cl- loading,our experimental results suggest that more Hg could be delivered to Arctic aquatic ecosystems by melted snow（smaller Hg（Ⅱ）red expected）, but the Hg in the melted snow that is photoreduced may do so more quickly（larger k expected）.

关键词： Mercury Photoreduction Arctic Melted snow

Assessing the utility of dissolved organic matter photoreactivity as a predictor of in situ methylmercury concentration

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Journal of environmental Sciences 2018年第6期30卷 160-168页

作者： Sara J.Klapstein Susan e.Ziegler David A.Risk Nelson J.O'driscoll environmental Science Program Memorial University of Newfoundland Department of earth Sciences St. Francis Xavier University Department of earth and environmental Science Acadia University

Methylmercury（MeHg） bioaccumulation is a growing concern in ecosystems worldwide. The absorption of solar radiation by dissolved organic matter（DOM） and other photoreactive ligands can convert MeHg into less toxic forms of mercury through photodemethylation. In this study, spectral changes and photoreactivity of DOM were measured to assess the potential to control photoreactions and predict in situ MeHg concentration. Water samples collected from a series of lakes in southwestern Nova Scotia in June, August, and September were exposed to controlled ultraviolet-A（UV-A） radiation for up to 24 hr. Dissolved organic matter photoreactivity, measured as the loss of absorbance at 350 nm at constant UV-A irradiation, was positively dependent on the initial DOM concentration in lake waters（r^2=0.94）. This relationship was consistent over time with both DOM concentration and photoreactivity increasing from summer into fall across lakes. Lake in situ MeHg concentration was positively correlated with DOM concentration and likely catchment transport in June（r = 0.77） but not the other sampling months. Despite a consistent seasonal variation in both DOM and Fe, and their respective correlations with MeHg, no discernable seasonal trend in MeHg was observed. However, a 3-year dataset from the 6 study lakes revealed a positive correlation between DOM concentration and both Fe（r = 0.91） and MeHg concentrations（r = 0.51） suggesting a more dominant landscape mobility control on *** DOM-MeHg relationships observed in these lakes highlights the need to examine DOM photoreactivity controls on MeHg transport and availability in natural waters particularly given future climate perturbations.

关键词： Methylmercury Dissolved organic carbon Photoreactions Kejimkujik National Park Freshwater lakes

Virus-Induced Gene Silencing in the Culinary Ginger （Zingiber officinale）： An effective Mechanism for Down-Regulating Gene expression in Tropical Monocots

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Molecular Plant 2009年第5期2卷 1084-1094页

作者： Tanya Renner Jennifer Bragg Heather e. driscoll Juliana Cho Andrew O. Jackson Chelsea D. Specht Department of Plant and Microbial Biology University of California Berkeley CA 94720 USA Present address: Genornics and Gene Discovery USDA ARS PWA WRRC-GGD 800 Buchanan Street Albany CA 94710 USA

Virus-induced gene silencing （VIGS） has been shown to be effective for transient knockdown of gene expression in plants to analyze the effects of specific genes in development and stress-related responses. VlGS is well established for studies of model systems and crops within the Solanaceae, Brassicaceae, Leguminaceae, and Poaceae, but only recently has been applied to plants residing outside these families. Here, we have demonstrated that barley stripe mosaic virus （BSMV） can infect two species within the Zingiberaceae, and that BSMV-VIGS can be applied to specifically down-regulate phytoene desaturase in the culinary ginger Zingiber officinale. These results suggest that extension of BSMV-VlGS to monocots other than cereals has the potential for directed genetic analyses of many important temperate and tropical crop species.

关键词： Barley stripe mosaic virus virus-induced gene silencing VIGS Zingiber officinale Monocot.

Mercury photoreduction and photooxidation in lakes：effects of filtration and dissolved organic carbon concentration

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Journal of environmental Sciences 2018年第6期30卷 151-159页

作者： Nelson J.O’driscoll emma Vost erin Mann Sara Klapstein Robert Tordon Matthew Lukeman Department of earth & environmental Science Acadia University Wolfville B4P 2R6 Nova Scotia Canada environment Canada Dartmouth Nova Scotia Canada Department of Chemistry Acadia University Wolfville B4P 2R6 Nova Scotia Canada

Mercury is a globally distributed, environmental contaminant. Quantifying the retention and loss of mercury is integral for predicting mercury-sensitive ecosystems. There is little information on how dissolved organic carbon（DOC） concentrations and particulates affect mercury photoreaction kinetics in freshwater lakes. To address this knowledge gap,samples were collected from ten lakes in Kejimkujik National Park, Nova Scotia（DOC： 2.6–15.4 mg/L）. Filtered（0.2 μm） and unfiltered samples were analysed for gross photoreduction, gross photooxidation, and net reduction rates of mercury using pseudo first-order curves. Unfiltered samples had higher concentrations（p = 0.04） of photoreducible divalent mercury（Hg（II）ReD）（mean of 754 ± 253 pg/L） than filtered samples（mean of 482 ± 206 pg/L）;however, gross photoreduction and photooxidation rate constants were not significantly different in filtered or unfiltered samples in early summer. DOC was not significantly related to gross photoreduction rate constants in filtered（R2= 0.43; p = 0.08） and unfiltered（R2= 0.02; p = 0.71） samples; DOC was also not significantly related to gross photooxidation rate constants in filtered or unfiltered samples. However, DOC was significantly negatively related with Hg（Ⅱ）ReD in unfiltered（R2= 0.53; p = 0.04）, but not in filtered samples（R2= 0.04;p = 0.60）. These trends indicate that DOC is a factor in determining dissolved mercury photoreduction rates and particles partially control available Hg（Ⅱ）ReD in lake water. This research also demonstrates that within these lakes gross photoreduction and photooxidation processes are close to being in balance. Changes to catchment inputs of particulate matter and DOC may alter mercury retention in these lakes and could partially explain observed increases of mercury accumulation in biota.

关键词： Mercury Photoreduction Photooxidation Dissolved organic carbon(DOC) Particulates Kejimkujik National Park

圣路易斯歌剧院的艺术女神——女高音歌唱家凯莉·卡杜斯

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歌剧 2008年第10期 33-37页

作者： e.paul driscoll 徐笑然

2008年6月，女高音歌唱家凯莉·卡杜斯在圣路易斯歌剧院，她歌唱梦想起步的地方，上演了她的经典角色——蝴蝶夫人巧巧桑。

关键词：女高音歌唱家歌剧院女神艺术

Mercury bioaccumulation in aquatic biota along a salinity gradient in the Saint John River estuary

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Journal of environmental Sciences 2018年第6期30卷 41-54页

作者： Bethany L.Reinhart Karen A.Kidd R.Allen Curry Nelson J.O’driscoll Scott A.Pavey Department of Biology and Canadian Rivers Institute University of New Brunswick Saint John Saint John New Brunswick E2L4L5 Canada Department of Biology Forestry and Environmental Management and Canadian Rivers Institute University of New Brunswick Fredericton New Brunswick E3B4A3 Canada Department of earth and environmental Sciences Acadia University Wolfville Nova Scotia B4P2R6 Canada Department of Biology and School of Geography & earth Sciences McMaster University Hamilton Ontario LSS 4K1 Canada

Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint John River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with *** aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint John River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.

关键词： Stickleback Amphipod Methylmercury Biomagnification Stable isotopes Food web

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美丽新世界:美国女中音伊莎贝尔·里奥纳多

歌剧 2013年第3期 38-42页

作者： F.paul driscoll 燕青

她叫伊莎贝尔·翌奥纳多十年前的这个时候，《歌剧新闻》发表了一篇题为“糖果店里的孩子们”的文章。2002年7月底，从曼哈顿音乐学院和茱莉亚音乐学院声乐系随机挑选的4名学生得到了《歌剧新闻》提供的每人100美元预算，任其在大都会... 详细信息

她叫伊莎贝尔·翌奥纳多十年前的这个时候，《歌剧新闻》发表了一篇题为“糖果店里的孩子们”的文章。2002年7月底，从曼哈顿音乐学院和茱莉亚音乐学院声乐系随机挑选的4名学生得到了《歌剧新闻》提供的每人100美元预算，任其在大都会歌剧院音像店选购CD。4位幸运儿被请到《歌剧新闻》的办公室，谈谈他们的购买心得。

关键词：伊莎贝尔女中音《歌剧新闻》美国世界大都会歌剧院音乐学院曼哈顿

Antiferromagnetism and p-type conductivity of nonstoichiometric nickel oxide thin films

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InfoMat 2020年第4期2卷 769-774页

作者： Mari Napari Tahmida N.Huq Tuhin Maity Daisy Gomersall Kham M.Niang Armin Barthel Juliet e.Thompson Sami Kinnunen Kai Arstila Timo Sajavaara Robert L.ZHoye Andrew J.Flewitt Judith L.MacManus-driscoll Department of Materials Science and Metallurgy University of CambridgeCambridgeUK electrical engineering Division Department of EngineeringUniversity of CambridgeCambridgeUK Department of Physics University of JyvaskylaJyvaskylaFinland Zepler Institute for Photonics and Nanoelectronics University of SouthamptonSouthamptonUK

Nickel oxide(NiO)is one of the most studied transition metal oxides due to its versatile chemical and electronic properties,enabling it to be used in a wide variety of *** its stoichiometric form,NiO is an antiferromagnetic insulator,with resistivity up to 10^13Ωcm.1 When Ni vacancies are introduced,the nonstoichiometric nickel oxide becomes a semiconductor.

关键词： atomic layer deposition chemical vapor deposition nickel oxide solution deposition thin films

elevated L-lactate Promotes Major Cellular Pathologies Associated with Neurodegenerative Diseases

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Neuroscience Bulletin 2021年第3期37卷 380-384页

作者： Andrew DChapp Jessica eBehnke Kyle Mdriscoll Taija Hahka Zoe LaLonde Zhiying Shan Qing-Hui Chen Department of Kinesiology and Integrative Physiology Michigan Technological UniversityHoughtonMI 49931USA Department of Biological Sciences Michigan Technological UniversityHoughtonMI 49931USA

Dear editor,Small,short-chain fatty acids(SCFAs)(acetic acid,propionic acid,and butyric acid:conjugate bases,acetate,propionate,and butyrate)as well as the alpha-hydroxy acid,L-lactic acid(conjugate base,L-lactate)are important energy substrates and signaling molecules in the central nervous system(CNS)[1,2].L-lactic acid is produced by glycolysis[3]and gut microbes[4]and is released in large quantities during exercise[5].

关键词： conjugate bases quantities

Sodium Diffuses from Glass Substrates through P1 Lines and Passivates Defects in Perovskite Solar Modules

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energy & environmental Materials 2023年第6期6卷 393-401页

作者： Felix Utama Kosasih Francesco Di Giacomo Jordi Ferrer Orri Kexue Li elizabeth M.Tennyson Weiwei Li Fabio Matteocci Gunnar Kusch Narges Yaghoobi Nia Rachel A.Oliver Judith L.MacManus-driscoll Katie L.Moore Samuel D.Stranks Aldo Di Carlo Giorgio Divitini Caterina Ducati Department of Materials Science and Metallurgy University of Cambridge27 Charles Babbage RoadCambridge CB30FSUK Centre for Hybrid and Organic Solar energy(CHOSe) Department of Electronic EngineeringUniversity of Rome Tor VergataRome 00133Italy Cavendish Laboratory University of CambridgeJJ Thomson AvenueCambridge CB30HEUK Department of Materials and Photon Science Institute University of ManchesterOxford RoadManchester M139PLUK Department of Chemical engineering and Biotechnology University of CambridgePhilippa Fawcett DriveCambridge CB30ASUK Laboratory for Advanced Solar energy(LASe) National University of Science and Technology MISiSLeninskiy Prospekt 4Moscow 119049Russia energy Research Institute@NTU Nanyang Technological University50 Nanyang DriveSingapore 637553Singapore MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China Istituto di Struttura della Materia-CNR(ISM-CNR) Via del Fosso del Cavaliere 100Rome 00133Italy electron Spectroscopy and Nanoscopy Istituto Italiano di TecnologiaVia Morego 30Genova 16163Italy

Most thin-film photovoltaic modules are constructed on soda-lime glass(SLG)substrates containing alkali oxides,such as Na_(2)*** may diffuse from SLG into a module's active layers through P1 lines,an area between a module's constituent cells where the substrate-side charge transport layer(CTL)is in direct contact with *** diffusion from SLG is known to cause several important effects inⅡ-Ⅵand chalcogenide solar modules,but it has not been studied in perovskite solar modules(PSMs).In this work,we use complementary microscopy and spectroscopy techniques to show that Na diffusion occurs in the fabrication process of *** diffuses vertically inside P1 lines and then laterally from P1 lines into the active area for up to 360 *** propose that this process is driven by the high temperatures the devices are exposed to during CTL and perovskite *** diffused Na preferentially binds with Br,forming Br-poor,l-rich perovskite and a species rich in Na and Br(Na-Br)close to P1 ***-Br passivates defect sites,reducing non-radiative recombination in the perovskite and boosting its luminescence by up to 5×.Na-Br is observed to be stable after 12 weeks of device storage,suggesting long-lasting effects of Na *** results not only point to a potential avenue to increase PSM performance but also highlight the possibility of unabated Na diffusion throughout a module's lifetime,especially if accelerated by the electric field and elevated temperatures achievable during device operation.

关键词： defect passivation monolithic interconnection perovskite solar modules soda-lime glass sodium diffusion solar cells thin-film photovoltaics